A slip ring assembly is provided on the rotatable rotor shaft of some types of electrical generating devices for effecting an electrical connection between the rotor of the device and associated, relatively fixed electrical contact brushes. Such an assembly typically includes an electrically non-conductive body which carries a pair of axially spaced, annular members referred to as slip rings. A pair of terminals are respectively electrically joined to the slip rings. The terminals typically extend axially from one end of the assembly, and are electrically joined to the windings of the rotor assembly. The slip rings are positioned for respective electrical contact with a pair of relatively fixed, non-rotating brushes, thus providing the desired electrical connection between the brushes and the rotor assembly. Such an arrangement is typical of the construction of an automobile alternator and like electrical current generating devices.
Slip ring assemblies of the above type have typically been manufactured by a compression molding process. Specifically, each of the slip rings of the assembly is formed and joined to a respective one of the pair of terminals. Each slip ring and its terminal are then positioned within a molding cavity, with the slip rings positioned in the desired axially spaced relationship. A charge of electrically non-conductive moldable material is then introduced into the mold cavity, and the mold cavity is closed so as to form the body of the slip ring assembly from the moldable material. During molding, the body is typically formed with an axial bore to facilitate mounting on the associated rotor shaft, with the moldable material flowing against the slip rings and their respective terminals to permanently affix the slip rings in the desired axially spaced relation while electrically isolating each slip ring and its respective terminal from the other.
While the above compression molding technique provides a slip ring assembly having the necessary functional characteristics, formation by compression molding is relatively inefficient and expensive when compared to injection molding manufacturing methods. It is thus highly desirable to provide a slip ring assembly for an alternator or like electrical apparatus which can be efficiently formed by injection molding.